we currently do load tests on a webapp ecommerce site based on Terracotta 3.5.3 DSO. For each successful login or logout a user session object gets added or removed from a clustered ConcurrentHashMap.
When increasing the load/threads we experience a high thread contention and the app slows down dramatically, probably caused by updating the ConcurrentHashMap. The thread dumps show many threads locked/blocked
on the CHM.

I read some blog posts about the org.terracotta.collections.ConcurrentDistributedMap and so I want to replace the existing implemention with it, but I am unable to accomplish that.
When updating or installing all tim-modules on the terracotta server (same for terracotta-3.6.1) I never see/get a tim-concurrent-collections downloaded nor installed
I found http://svn.terracotta.org/svn/forge/projects/tim-concurrent-collections/tags/release-1.3.4, but I am unsure if I need to build it myself. The documentation somehow is misleading.

http://www.terracotta.org/confluence/display/docs/DSO+Data+Structures+Guide "Since CSM is not a standard Java data type, you must include the Terracotta Integration Module (TIM) tim-concurrent-collections as a library to access the class. You must also add tim-concurrent-collections to the Terracotta configuration file. See the Configuration Guide and Reference for more information on how to configure TIMs in Terracotta."

No module found matching the arguments specified: tim-concurrent-collections
Check that you've spelled them correctly or are in the right order.

Same issue when using the Terracotta eclipse plugin. After updating all modules the tim-concurrent-collections is never shown.
Is it still supported? Can somebody advise me on how to use ConcurrentDistributedMap? Thx and it is urgent;-)